Online Dice Roller Guide: d6, d20 and Dice Notation Explained
Board games, tabletop RPGs and probability lessons all need dice — and a virtual roller is always in your pocket. Here’s how dice notation works and what to expect from your rolls.
Dice notation in one minute
NdS means “roll N dice with S sides and add them”. 2d6 is two six-sided dice (Monopoly, Catan); 1d20 is the iconic D&D check; 1d100 (percentile) handles percentages.
Why 7 is the most common 2d6 total
There are 36 combinations of two dice and six of them total 7 (1+6, 2+5, 3+4…), giving a 16.7% chance. Totals of 2 and 12 have only one combination each (2.8%). That’s why the robber in Catan moves on a 7.
Fair rolls, every time
Physical dice can be weighted or worn; virtual dice are perfectly balanced. Roll up to 20 dice at once with automatic totals — perfect for damage rolls and big board-game turns.
Pro tips
- Six-sided dice show pips; other dice show numbers.
- Use the total line to avoid adding up by hand.
- For “yes/no” decisions, the Coin Flip is quicker.